1. Field of the Invention
The present invention relates to a mobile communication device, and more particularly to a mobile communication device for receiving radio alarm warnings.
2. Description of the Related Art
Uncontrollable natural disasters such as tornados, downpours, and floods or sudden man-made disasters such as wars and terrorist attacks are often unpredictable and sacrifice numerous lives or cause heavy damage to civil property. Therefore, many countries set up a radio alarm systems for notifying the public of alarm warnings as soon as possible. Thus, the public can take appropriate measures in a timely manner to prevent danger or be evacuated from dangerous areas to reduce the impact of the disaster, thus lives and civil and private property can be protected.
Presently there are two kinds of radio alarm systems, one is to broadcast alarm warnings with loudspeakers, and the other is to broadcast alarm warnings with radio signals received by televisions, radio sets, or alarm receivers. The former is limited by the number and area covered by the loudspeakers, and is useless when the dangerous areas exceed that covered. The latter is currently the most efficient radio alarm system. For example, the national oceanic and atmosphere administration (NOAA) has more than 900 national weather service radio locations for broadcasting alarm warnings to a coverage area encompassing the United States.
Nevertheless, the alarm warnings of the latter radio alarm system can only be heard when there is a television or a radio set nearby. Thus, the influence of the radio alarm system using televisions or radio sets is limited. In addition, most of the alarm receivers are not portable, and ordinary people will not typically carry an alarm receiver even if the alarm receiver is portable. Therefore, it is difficult for people to always receive alarm warnings when disasters occur.
Presently there is an attempt to receive alarm warnings through mobile communication devices. This attempt utilizes the base stations of telecommunication service providers to send audio warning messages to mobile communication devices of receivers. However, the reception coverage is limited by the strength of communication signals and setting area of the base stations. The reception coverage of the base stations is far more restricted than that of radio broadcasting, and it is impossible to receive audio warning messages at places where there is no base station. In addition, the government cannot know the precise location of individuals and fails to send audio warning messages to them in a timely manner.